The sentence is the smallest fragment able to communicate an idea.This is a serie of words that have complete sense. The sentence is independent from the point of view of grammar (do not need more things to be understand) and ends at a pause or at one point.
Te sentence consists of:
Subject. The person, animal or thing that performs the action of the verb or something is said: Marta come hamburguesas (the subject is Marta). Marta es bonita (the subject is Marta).
The subject is always a noun or any other word that functions as if it were a noun.
To know what is the subject of a sentence asks “who?” to the verb.
Predicate. It is indicating what the subject makes or what is said of the subject (The person, animal or thing): Marta come hamburguesas (the predicate is come hamburguesas). Marta es bonita (the predicate is es bonita).
The most important word in the predicate is the verb.
To know what is the predicate of a sentence simply remove the subject, for whatever subject is not predicate.
The subject and predicate always agree in number and person: Marta is singular and the verb come is singular. Marta is the third person singular (ella) and the verb come is in the third person singular (ella come)
There are two basic types of sentences.
Simple: with one verb
Juan estudia mucho
Los turistas visitan museos
María viajó a París
Los libros llegarán mañana
Carolina es profesora
Composite: two or more verbs
Juan estudia por la mañana y juega por la tarde
Los turistas visitan museos y comen en restaurantes
María viajó a París, visitó a sus amigos y compró libros
Los libros llegarán mañana y los venderán pasado mañana
Carolina es profesora y su esposo es médico